1. Field of the Invention
The present invention relates to a data conversion method and a data conversion device, and more particularly to a data conversion method and a data conversion device for three-dimensional images.
2. Related Art
A three-dimensional image capture device may be used to capture three-dimensional images in a space. The captured three-dimensional images may be stored or transmitted after being digitalized.
The three-dimensional image capture device and relevant techniques may be used in medicine, security, disaster relief, and other public welfare purposes, or in distant video transmission, audio visual entertainment, and other daily life purposes. The technique has a wide application scope.
Generally, the three-dimensional image captured by the three-dimensional image capture device has high dimensions, such that the image has a larger data volume, resulting in inconvenience in transmission or storage. Therefore, a three-dimensional image compression device is required to compress the three-dimensional image to reduce the data volume. However, the data unit compressed by the three-dimensional image compression device each time is quite limited. Therefore, a conversion device is required to convert a piece of large cubic three-dimensional image data to a plurality of pieces of small cubic one-dimensional image data.
When being stored or transmitted, the three-dimensional image information is converted to a data stream, that is, an address is marked on each data of the three-dimensional image information. Firstly, the addresses are marked on the data in sequence along a first dimension, that is, the addresses are marked along a straight line direction. After the information on the straight line is completely marked, the information on a next straight line on the same plane is marked. After all the information on the plane is marked, the information on a next plane is marked continuously. As such, all the data is marked in sequence. Through the marked addresses, the three-dimensional image information is converted to a data stream sequenced according to the marked addresses, and the three-dimensional image information may be stored or transmitted according to the marked addresses.
Before the compression, a large three-dimensional image data is converted to a plurality of pieces of small three-dimensional image data. The small three-dimensional image data crosses a plurality of straight lines and planes. That is, the addresses corresponding to the small three-dimensional image data are distributed quite discretely.
In a data conversion method in the prior art, a buffer memory having a very large memory capacity is used. After the three-dimensional image data is completely stored to the buffer memory, the data corresponding to each small cubic one-dimensional image are fetched. Usually, the capacity of the memory is proportional to the area thereof. Therefore, in order to implement the data conversion method in the prior art, a memory having a large area is required. In addition, at a fixed access speed, the data conversion method in the prior art also has a long latency, thereby affecting the performance of the entire system.